vagrant: add a OpenBSD 7.7 box

The base box has an invalid hostname and no comp package installed,
so we need to fix that.

Vagrantfile

@@ -72,7 +72,15 @@ end
 
 def packages_openbsd
   return <<-EOF
+    hostname "openbsd77.localdomain"
+    echo "$(hostname)" > /etc/myname
+    echo "127.0.0.1	localhost" > /etc/hosts
+    echo "::1 localhost" >> /etc/hosts
+    echo "127.0.0.1	$(hostname) $(hostname -s)" >> /etc/hosts
     echo "https://ftp.eu.openbsd.org/pub/OpenBSD" > /etc/installurl
+    ftp https://cdn.openbsd.org/pub/OpenBSD/$(uname -r)/$(uname -m)/comp$(uname -r | tr -d .).tgz
+    tar -C / -xzphf comp$(uname -r | tr -d .).tgz
+    rm comp$(uname -r | tr -d .).tgz
     pkg_add bash
     chsh -s bash vagrant
     pkg_add xxhash
@@ -80,7 +88,7 @@ def packages_openbsd
     pkg_add zstd
     pkg_add git  # no fakeroot
     pkg_add rust
-    pkg_add openssl%3.0
+    pkg_add openssl%3.4
     pkg_add py3-pip
     pkg_add py3-virtualenv
     echo 'export BORG_OPENSSL_NAME=eopenssl30' >> ~vagrant/.bash_profile
@@ -373,7 +381,7 @@ Vagrant.configure(2) do |config|
   end
 
   config.vm.define "openbsd7" do |b|
-    b.vm.box = "generic/openbsd7"
+    b.vm.box = "l3system/openbsd77-amd64"
     b.vm.provider :virtualbox do |v|
       v.memory = 1024 + $wmem
     end